ARM hits power-draw low with Cortex-M0+

ARM's new Cortex-M0+ draws around a third the power of similar 8-bit and 16-bit microprocessors, despite a full 32-bit ARM ISA.

British chip giant ARM has announce its lowest power processor design yet, the 32-bit Cortex-M0+ which draws just 9µA per megahertz clock speed.

Designed for embedded applications, the Cortex-M0+ builds on the existing Cortex-M family with a new low-power design based on the ubiquitous and low-cost 90nm manufacturing process. While its performance and capabilities aren't quite up there with the Cortex-A9 family, as found at the heart of most mobile and tablet implementations, it certainly can't be beat on power draw.

According to ARM, the Cortex-M0+ processor draws just 9µA per megahertz, about a third of the energy of competing 8-bit and 16-bit microprocessor designs. This is despite the Cortex-M0+ featuring a full 32-bit implementation of the ARM reduced instruction set (RISC) architecture.

The result, ARM claims, is a chip which offers the the power and flexibility required to develop complex networks of autonomous and self-powered sensors. In other words: ARM is positioning itself as the brain at the heart of the Internet of Things.

'The Internet of Things will change the world as we know it, improving energy efficiency, safety, and convenience,' claimed Tom Halfhill, a senior analyst with The Linley Group and senior editor of Microprocessor Report, in a statement supporting ARM's launch. 'Ubiquitous network connectivity is useful for almost everything - from adaptive room lighting and online video gaming to smart sensors and motor control. But it requires extremely low-cost, low-power processors that still can deliver good performance. The ARM Cortex-M0+ processor brings 32-bit horsepower to flyweight chips, and it will be suitable for a broad range of industrial and consumer applications.'

'The Cortex-M0+ processor is yet another demonstration of ARM low power leadership and its commitment to drive the industry forward towards ever lower power consumption,' claimed Mike Inglis, general manager of ARM's processor division, at the launch. 'With our expertise in low-power technology, we have worked closely with our partners on the definition of the new processor to ensure that it can enable the low-cost devices of today, while also unlocking the potential benefits delivered by the Internet of Things.'

Thanks to its basis in the Cortex-M family, the new Cortex-M0+ can run any code written for the Cortex-M series of processors. This includes the higher-performance and more power-hungry Cortex-M3 and M4 series, giving programmers a way to migrate their low-power systems to a more powerful platform as and when required.

At launch, the Cortex-M0+ will be supported by ARM's Keil Microcontroller Development Kit as well as third-party tools from the likes of CodeSourcery, Code Red, Express Logic, IAR Systems, Mentor Graphics, Micruim and SEGGER. ARM has named two licensees of the technology thus far: Freescale and NXP Semiconductor.

Thus far, however, neither partner has offered pricing details for the chip. The Cortex-M0+ promises much but if it fetches too much of a premium over existing 8-bit and 16-bit microcontroller solutions from the likes of Texas Instruments and Atmel, it could find itself priced out of the market.